Catheters for medical procedures such as the well known PTCA procedure are desirably rotatable at their distal ends while positioned within the blood vessel of a patient. This may be accomplished by providing to the catheter a longitudinally positioned steering wire, which facilitates steering of the catheter by stiffening it rotationally so that rotation of the proximal end of the catheter will cause rotation of the distal end as well. Then, if the distal end of the catheter has a curve in it, rotation of the catheter can cause the curved end to rotate as well, to assist in directing the catheter into the proper blood vessel when a blood vessel junction is encountered, or the like.
Typically, blood vessel catheters of the prior art carry a hub at their proximal end, and also a branched connection along the length of the catheter which terminates in a second hub. For example, in a PTCA catheter, one of the hubs may be used to secure the longitudinal steering wire which permits rotation of the distal end of the catheter when emplaced in the blood vessel. The other hub carries a port which communicates with an inflation balloon in the catheter. In the case of a PTCA catheter, this is for dilating sclerotic lesions in arteries after the catheter has been properly emplaced.
In accordance with this invention, a simplified, effective catheter is provided, primarily for medical purposes such as PTCA, in which a single hub may provide the combined functions of proximal mounting for a steering wire, plus a connection site for an inflation lumen which communicates with a balloon in the catheter. The connection site of the inflation lumen may be, for example, a simple luer-type connection through which a syringe may inject an inflation fluid to inflate the balloon, for example a 50/50 mixture of X-ray contrast media and saline solution. Thus, the catheter of this invention is substantially simplified from prior art catheters of equivalent function, having one hub rather than two hubs plus a branched connection. Nevertheless, the catheter may exhibit excellent steerable qualities by means of the longitudinal wire carried therein, while also carrying an inflation balloon.
The catheter of this invention exhibits a novel connection between the longitudinal steering wire carried therein and the hub to which it is attached, to accomplish the purposes of this invention.